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     <td><h1 class="pagetitle">Character Entities</h1>
         <b class="alert">End Tag:</b> <span class="magicword">NA</span><br>
         <b><a href="../../../misc/suppkey.htm">Support Key:</a></b> 
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         [<b class="s">IE1</b>|<b><i class="fs">M1</i></b>|<b class="s">N1</b>|<b class="s">O2.1</b>]</td>
     <td><a href="#what">What is it?</a><br>
         <a href="#attrib">Attributes</a><br>
         <a href="#example">Tag Example</a>
     </td>
     <td><a href="#model">Parent/Content Model</a><br>
         <a href="#tips">Tips &amp; Tricks</a><br>
         <a href="#peculiar">Browser Peculiarities</a></td>
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<a name="what"></a>
<dl>
<dt><big><b class="mainheading">What is it?</b></big>
    <dd>A text character usually lives as an Octet, which is a single byte
        or 8 bits of data. Using 8 bits allows for 256 (a range from 0-255)
        possible distinct character codes. While the HTTP protocol allows the full
        256 character range of the ISO 8859-1 (ISO Latin) characters to be
        transported, not all operating systems or applications may natively support
        this range. In order to increase portability and viewability of this character
        set on all browsers, HTML offers alternative representations of all the ISO
        Latin characters using coded Character Entities (see index below.) These
        case-sensitive, coded representations are created using characters from a
        proper subset of the ISO Latin  character set known as
        <a href="../t/text.htm#ascii">ASCII</a>.
        <br><br>
   
        Included in the Character Entity domain are both numbered and named entities:
        <dl>
        <dt><b class="magicword">Numbered Entity Syntax:</b>
            <b class="alert">&amp;#charnumber;</b>
            <dd>Where <em>charnumber</em> is a distinct integer from 0-255.
        <dt><b class="magicword">Named Entity Syntax:</b>
            <b class="alert">&amp;charname;</b>
            <dd>Where <em>charname</em> is a unique mnemonic shorthand of
                the character to be represented.
        </dl>
        <br>
        <b class="alert">Note:</b> The trailing semi-colon character (';') is only
        <em>necessary</em> if the character following the entity reference would
        be recognized as part of the entity. Even so, it is probably wise to
        <em>always</em> use this trailing termination character to be consistent.
</dl>

<dl>
<dt><br><big><b class="mainheading">Character Entity Indexes</b></big>
<dt><a name="iso88591"><b class="subheading">The ISO-8859-1 Character Set</b></a>
    <dd><a href="../entities/charentity0-31.htm">000-031</a> |
        <a href="../entities/charentity32-64.htm">032-064</a> |
        <a href="../entities/charentity65-96.htm">065-096</a> |
        <a href="../entities/charentity97-126.htm">097-126</a>
    <dd><a href="../entities/charentity127-159.htm">127-159</a> |
        <a href="../entities/charentity160-191.htm">160-191</a> |
        <a href="../entities/charentity192-223.htm">192-223</a> |
        <a href="../entities/charentity224-255.htm">224-255</a>

<dt><br><a name="unichars"><b class="subheading">Unicode Character Entities</b></a>
    <dd><a href="../entities/arrow.htm">Arrows</a> - Arrow Shapes
    <dd><a href="../entities/greekcapitals.htm">Greek Capitals</a> - Greek capital characters
    <dd><a href="../entities/greeksmalls.htm">Greek Smalls</a> - Greek 'lower case' characters
    <dd><a href="../entities/math.htm">Math Symbols</a> - Characters commonly used in mathematics
    <dd><a href="../entities/miscletters.htm">Miscellaneous letters</a> - Latin Extended-A
        and B characters and Letter-like Symbols
    <dd><a href="../entities/miscshapes.htm">Miscellaneous shapes</a> - Playing card suit
        symbols and other graphical symbols
    <dd><a href="../entities/misctechnical.htm">Miscellaneous technical symbols</a> -
        Characters used in various technical disciplines
    <dd><a href="../entities/spacebidi.htm">Bi-directional and spacing characters</a> -
        Characters used to control bi-directional text and text spacing
    <dd><a href="../entities/genpunctuation1.htm">General punctuation set 1</a> -
        Commonly used punctuation characters
    <dd><a href="../entities/genpunctuation2.htm">General punctuation set 2</a> -
        More commonly used punctuation characters
</dl>


<a name="attrib"></a>
<dl>
<dt><br><big><b class="mainheading">Attributes</b></big>
    <dd><b class="alert">Character Entities do not accept attributes</b>
</dl>


<a name="example"></a>
<dl>
<dt><big><b class="mainheading">Example</b></big>
    <dd><div class="example"><b class="tagname">&amp;Agrave;</b> = &Agrave;</div>
</dl>


<a name="model"></a>
<dl>
<dt><big><b class="mainheading">Parent Model</b></big>
    <dd><b class="alert">%<a href="../shorthands.htm#inlineparent">In-line Parent</a>%</b> |
        <b class="alert">%<a href="../shorthands.htm#blockparent">Block Parent</a>%</b> |
        &lt;<a href="../d/del.htm">Del</a>&gt; |
        &lt;<a href="../i/ins.htm">Ins</a>&gt; |
        &lt;<a href="../l/legend.htm">Legend</a>&gt; |
        &lt;<a href="../o/option.htm">Option</a>&gt; |
        &lt;<a href="../s/script.htm">Script</a>&gt; |
        &lt;<a href="../s/style.htm">Style</a>&gt; |
        &lt;<a href="../t/textarea.htm">Textarea</a>&gt; |
        &lt;<a href="../t/title.htm">Title</a>&gt;
<dt><big><b class="mainheading">Content Model</b></big>
    <dd><b class="alert">Character Entities do not accept content.</b>
</dl>


<a name="tips"></a>
<big><b class="mainheading">Tips &amp; Tricks</b></big>
<ul>
    <li>Character entities can be used anywhere regular characters will be
        displayed on screen.
    <li>In cases like IMG or INPUT, entities are used only for final display
        purposes (ALT text for Images or VALUE for Input elements.)
    <li>Entities are not to be used in path names for URLs.
    <li><b class="alert">DTD Note:</b> The &amp;quot; named character
        entity was retracted from the HTML 3.2 DTD. There is still some confusion
        as to <em>WHY</em> this was done, as this entity is in wide use, and exists in the
        HTML 2.0, 3.0 and 4.0 DTDs. There are two differing stories as to why
        it was deleted from the 3.2 DTD:
        <ol>
            <li>Dan Connolly (co-author of HTML 2.0) has said the omission was a mistake.
            <li>Dave Raggett (author of HTML 3.0, 3.2 and 4.0) has said that the
                omission was intentional due to a disagreement in the HTML ERB over
                which entities should be in HTML 3.2. Only the basic set of entities was
                agreed upon. (Many thanks to a reader who sent me some mail clarifying this.)
         </ol>
         Any documents using &amp;quot; will generate validation errors under the HTML
         3.2 DTD, but it should be safe to leave these entities in legacy documents
         due to wide legacy and future browser/DTD support. The alternate form of this
         entity ('&amp;#34;') <em>WILL</em> validate and should be considered when
         authoring new documents.
</ul>

<a name="peculiar"></a>
<big><b class="mainheading">Browser Peculiarities</b></big>
<ul>
    <li>Internet Explorer 1.0-3.0 treated character entities case-insensitively,
        such that "&amp;EacuTE;" was treated the same as "&amp;eacute;" In IE4.0+,
        character entities are correctly case-sensitive.
    <li>IE seems to be VERY lenient on character entity parsing - it will allow
        an author to leave off the trailing semi-colon in every case that I have tried,
        whereas the Netscape 4.x+ and Opera browsers I tried choked the same way
        for the same test cases about half the time (Netscape/Opera could handle
        *&amp;nbsp.test*, *&amp;nbsp test*, and *&amp;nbsp&amp;nbsp;test*, but they
        couldn't handle *&amp;nbsptest*, *&amp;nbsp1test*, *&amp;nbspptest*,
        *&amp;nbsp99test* and *&amp;nbsp&amp;nbsptest*.) IE handles <em>ALL</em>
        of these cases just fine and renders all of the attempted non-breaking
        spaces. I leave it to the reader to infer equivalence classes for this
        behavior, but the gist of this item is: don't forget the semi-colon!
</ul>


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